It’s not some force keeping them the same, it’s no force changes the speed of the moon. From my limited understanding the moon was created when a smaller planet crashed into the earth:
They both got the same momentum, therefor they started rotating at the same speed, once per day.
There is nothing out there which would be able to change the speed of the rotation of the moon. There is also nothing which would change the speed of the rotation of the earth. Therefor they keep spinning at the same speed.
Other people have explained it, and the same thing happens with other moons in the solar system, including some orbiting gas giants where your explanation couldn’t have worked.
The Earth’s gravitational field elongates the moon slightly, and an elongated satellite tends more to stabilize its rotation with the longer diameter fixed to point at the center of its orbit.
Not my field, but I don't think it's even possible to really pinpoint "the" most recent evolutionary step, not to mention being able to define "step" in an incredibly slow variable with multiple layers of continuity (individual, population, and whole species levels).
But I would say that it is very recent for sure, as lactase persistence is a trait that really only started (above "noise" level stochastic mutations in the population) when we started using dairy some 6000 years ago because of selection pressure.
Try recreating that spin with a fidget spinner and slowly turn it around like the moon turns to face earth. You’ll find that it wants to turn in a way where it spins around the same axis it’s orbiting.
Since the moon has no hand preventing it from doing that, it aligns its spin with the orbit, so the forces described in the article bring that rotation to a halt.
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